| Acquisition of USU (Tables) | 12 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Business Combinations [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Estimated Fair Value of Assets Acquired and Liabilities Assumed | The following is a summary of the estimated fair value of the assets acquired and liabilities assumed at the date of acquisition: 
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| Supplemental Unaudited Pro Forma Combined Information | The following supplemental unaudited pro forma combined information assumes that the acquisitions had occurred as of the beginning of each period presented: 
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- Definition Tabular disclosure of pro forma results of operations for a material business acquisition or series of individually immaterial business acquisitions that are material in the aggregate. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef 
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- References No definition available. 
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- Definition Tabular disclosure of the amounts recognized as of the acquisition date for each major class of assets acquired and liabilities assumed. May include but not limited to the following: (a) acquired receivables; (b) contingencies recognized at the acquisition date; and (c) the fair value of noncontrolling interests in the acquiree. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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